docs: def _from_bytes(self, byte_data, key=''):
          """Deserialize (and decrypt if key is provided) cached
          data stored in the byte_data (bytes object).
  
          # TODO: Full description of the method needed
  
          :param sdata: a string
          :param key: if provided (e.g. non-empty string), it
                      will be used to decrypt `sdata` as a password
          :type key: str, default is empty string
          :returns: a python object
          """
  
          if not can_encrypt and key:
              result = decode_safely(byte_data)
          elif can_encrypt and key:
              cipher = AESCipher(key)
              result = decode_safely(cipher.decrypt(byte_data))
          else:
              result = decode_safely(byte_data)
          return result